Thought I heard that trumpet noise once, but a friend explained what I might have heard instead. Was driving on I 40 late at night through eastern Arizona. The outside temperature was too low for me to stop and find a motel, due to reasons that are best left unexplained. At any rate, there seemed to be no motels or hotels in that area east of Flagstaff anyway. Ended up in that situation due to I 20 being closed from a West Texas wildfire.
So I ended up stopping at a Truck Stop Complex and just resting in the van over night. Got some rest. The weird thing was when I awoke there was a strange sound similar to the trumpet sound and the ground seemed to be oscillating with the sound. And I remembered hearing that all night long as a background noise. Kinda freaked me out. Later on my truck driving friend explained what might have happened. He pointed out that there could have been some strange oscillation between the nearby trucks running or idling. That did make sense, but I was really spooked out for awhile especially when I found out the Truck Stop was at an Indian reservation. That noise kinda sounded like pow wow music and the ground was vibrating with the sound.
Just thought I would share that with you as there are many alternative explanations to the strange trumpet like sounds.
Not as musical as the YouTube recordings on the subject, but the vibration transmitted was marked and unmistakeable, felt like it went right through you...although tbe volume of the sound rose and fell, tbe vibration was constant.
Given our freak wings and waterspouts that day, it seemed like a hypervelocity "river of wind" was overhead, and the friction with tbe more stable atmosphere made the bizarre sounds and vibrations...my theory, anyway.